Blow-out preventer



Nov. 12, 1957 E. J. ALBAREs 2,812,819

BLOW-OUT PREVENTER Filed Dec. 3. 1954 FIG. 2

3| IN VEN TOR.

-E. J. ALBARES ATTORNEYS 2,812,819 Patented Nov. 12, 1957 2,812,819BLOW-OUT PREVENTER Edwin J. Albares, Thibodaux, La., assignor toPhillips Petroleum Company, a corporation of Delaware ApplicationDecember 3, 1954, Serial No. 473,011 4 Claims. (Cl. 166-92) Thisinvention relates to drill hole blow-out preventers for use ingeophysical prospecting drill holes. In one aspect it relates to anapparatus which permits venting of gas while retaining solid matterblown from geophysical drill holes. In another aspect it relates to suchan apparatus which possesses safety features for the protection of theoperator.

In some areas of Louisiana it has been found that gas deposits occurwithin 30 to 40 feet of the earths surface and such shallow deposits ofgas frequently blow-out sand and shale from geophysical drill holesfollowing shooting of the holes. If precautionary measures are not takengas blowing from such drill holes frequently blow-out large quantitiesof sand and shale. In case the geophysical prospecting is being carriedout on agricultural land, the matter blown-out from the drill hole mayhave to be removed so as not to interfere with agriculture. In oneinstance a geophysical drill hole in a sugar cane field, after beingshot in the usual manner, blew out sand and shale to the extent of 22truck loads.

An object of my invention is to provide an apparatus for preventing theblow-out of solid material from drill holes after shooting.

Another object of my invention is to provide an apparatus for use inpreventing the blow-out of sand and shale from geophysical drill holesfollowing shooting.

Still another object of my invention is to provide a relativelyinexpensive and easy to use apparatus for preventing blow-out of solidmaterial from geophysical drill holes following shooting.

Still other objects and advantages of my invention will be realized uponreading the following description, which taken with the attacheddrawing, forms a part of this disclosure.

In the drawing:

Figure 1 represents, in diagrammatic form, one embodiment of apparatusof my invention.

Figure 2 is an elevational view, partly in section, of anotherembodiment of my apparatus.

Figure 3 illustrates another embodiment of a portion of my apparatus.

Figure 4 is a sectional view of another portion of my apparatus.

Figure 5 is an elevational view in section, of still another embodimentof a portion of my apparatus.

Referring now to the drawing and specifically to Figure 1 referencenumeral 17 identifies the surface of the ground into which a bore hole11 is drilled. The drilling operation for producing this bore hole iscarried out by use of drilling equipment commonly used by geophysicalprospecting parties. The type of this drilling apparatus can be anysuitable type desired to be used by a drilling crew.

In some instances the drill hole is cased with a tubing as the hole isbeing drilled. Under other conditions a hole is cased after the drillingoperation is complete. However, in areas containing surface deposits ofloose material, such as sand, it preferable to case the hole as it isbeing drilled. In some cases it is desirable to drill the hole with adrill bit attached to the bottom end of' a drill tubing, the drill beingadapted to drill a hole of larger diameter than that of the drilltubing. In this case the hole is usually cased with another tubing ofdiameter about the same as the drfll bit and as the drill hole advances.In any event, after the drilling is completed an explosive charge islowered into the hole and is detonated. In some areas, as in Louisiana,as mentioned, gas occurs in pockets at distances no greater than thedepth ordinarily reached in such drill holes. When a drill hole tapssuch shallow gas in sandy areas, large quantities of sand are sometimesblown from the hole following shooting. In order to prevent the blowingout of large quantities of sand and shale from a gas-containing depositidentified by reference numeral 18, I attach a pipe section 13, as by acollar 14, to the top of tubing 12. The upper end of the pipe section 13is provided with a cap 15 prior to attaching to the well tubing. Thispipe section 13 is provided with one or more openings 16. When usingsuch an apparatus as illustrated in Figure l the cap 15 is threaded orwelded, as illustrated in Figure 5, or is hinged as illustrated inFigure 3, as desired, to the top end of the pipe section 13. After thewell is shot the operator approaches the well with this piece ofequipment and threads it by means of collar 14 to the top end of thewell tubing. It is believed that the space above the openings 16 andbelow the cap 15 (Fig. 1) acts as a trap or as a solid materialseparator. Gas containing solid material flows upwardly through the welltubing 12, the solid material continues to move upward beyond theopenings 16 While the gas vents from the openings 16 to the atmosphere.Under some conditions it is preferable to employ a deflector such asdeflector 33 of Figure 2, or deflector 51 of Figure 4 as a safety meansfor the protection of the operator. Such a deflector is attachedpreviously, as by welding, to the pipe section 13 so that the operatorinstalling the blow-out preventer will be protected against solidmaterial blown through openings 16.

Solid material which is blown to the upper end of the pipe section 13drops downward in the pipe and tends to retard the upward flow of gasand solid material. When the volume of the pipe section 13 aboveopenings 16 is relatively large the solid material from that sectionfalls down the tubing and exerts a marked damping effect to the upwardflow of gas and in many instances seals off the hole from further flowof gas.

In Figure 2 is shown an embodiment of my invention involving anadditional safety device and also a large space between openings foroutflow of gas and the top end of the blow-out apparatus. In this figurea pipe section 31 contains openings 32 for outlet of gas. The bottom endof this tube is provided with threads for attaching to a drill holetubing such as tubing 12 of Figure 1. The deflector 33 is attached tothe pipe, as by welding, at such a position that solid material leavingthe pipe with the gas will impinge against the underside of thedeflector and be thrown downward toward the ground in place of outwardin the direction of an operator. To the upper end of pipe section 31 isattached a valve 35 by means of a nipple, and collar 34. When using sucha valve, the valve, being opened as by a hand wheel 36, and pipe section31 are attached to the top of the drill hole tubing. This apparatus isinstalled on the drill tubing prior to shooting of the hole. Afterinstalling this apparatus on the tubing, the shooting charge is loweredinto the hole through the valve and with the wires protruding from theupper portion of the valve. With the valve fully open the charge isdetonated. After detonation, if the drill hole blows solid material thevalve 35 is closed. When valve 35 is closed gas emerges from openings 32under the deflector 33, and while the valve is still closed another pipesection 40 with its upper end closed by a cap 41 is installed as by acollar 39 to the valve. By providing the valve 35 and having it closed,additional safety is provided for the operator whose'task it is toinstall capped pipe 40. When this pipe 40 has been installed, the valve35 is then opened with the result that a relatively large cavity isprovided above openings 32 for separation of solid material from thehigh pressure gas. By providing such a large volume, large quantities ofsolid material can accumulate therein and the solid material can thenfall downward and when the volume of this solid material is suflicientlygreat it may even seal off the drill hole against further flow of gas.

Under some conditions the drill hole may not be completely sealedagainst further flow of gas by the weight of a solid material but itsweight is sufficiently great as to markedly restrict the flow of gas.The apparatus of Figure 2 and of Figure 1 is allowed to remain attachedto the upper end of tubing 12 until such time that the bore hole ceasesto vent appreciable quantities of gas. When gas flow ceases the blowoutpreventing apparatus is removed from the bore hole tubing and taken toanother location for subsequent use.

While I have shown in Figures 1 and 2 the upper end of the pipe sections13 and 40 as being closed by threaded caps and 41, respectively, the useof threaded caps is not necessary since other suitable types of closuremeans can be used. One other type of closure means is illustrated inFigure 3 and this involves use of a plate 53 attached by hinged hasps. Ahinge element 54 comprises an eye 61 over which a hasp 62 is positionedprior to welding eye 61 to pipe section 52. Another eye 56 is attachedto the opposite side of pipe 52 in such a manner as to accommodate ahasp 55 attached to the plate 53. A bolt 57 is provided for insertingthrough eye 56 after hasp 55 is in place in order to hold the plate 53tightly against the upper end of pipe 52. This embodiment of pipeclosure is used with the embodiment of apparatus illustrated in Figure1, and it is also used with the embodiment of apparatus illustrated inFigure 2, when desired.

In Figure 4 is illustrated a type of deflector 51 which is used fordeflecting solid material emerging from openings 16 or 32 for the safetyof the operator. The embodiment of deflector of Figure 4 is possibly alittle simpler to manufacture than is a deflector 33 of Figure 2 and forthis reason alone such a deflector as that of Figure 4 may be preferred.

Still another closure means can be used for closing the upper end ofpipes 13 and 40, such a closure means is illustrated in Figure 5. Thisclosure means merely comprises a plate 58 attached by weld 60 to theopen end of a pipe 59. This pipe 59 then replaces pipe 40 of Figure 2 orwhen provided with openings for venting of gas it replaces pipe 13 ofFigure 1.

In one instance in which a drill hole tubing or casing was a 3 inchdiameter casing and its upper end extended to a level about one footabove the earths surface, a capped pipe similar to pipe 13 was threadedby a collar similar to collar 14 to the upper end of the drill holetubing. The pipe corresponding to pipe 13 contained a number of drillholes about one inch in diameter. The pipe was about 10 feet in length.The use of such a 10 foot long 3 inch diameter capped pipe with a numberof one inch diameter holes for venting of gas was used satisfactorily inpreventing the scattering of sand from a geophysical bore hole.

Many times sand blown from such bore holes is blown in slugs, that is,gas will blow relatively freely then all of a sudden a large quantity ofsand will accompany the gas. In this case the use of such an apparatusas that illustrated in Figure 2 with the blowout preventing pipe havinga large volume above the vent openings is especial- 1y useful. The slugof sand on flowing upward through the tubing in the bore hole at a rapidrate flows beyond the openings 32 while the gas flows out of theseopenings. When a large quantity of sand reaches this upper pipe itsweight then causes it to fall more or less as a mass and frequently sucha large mass of sand falling down the tubing plugs or at least restrictsthe bore hole against further flow of high pressure gas.

As mentioned above the pipe section 31 and valve 35 of the apparatus ofFigure 2 can be installed on the bore hole tubing and then the explosivecharged fired. If the bore hole does not blow sand the upper capped pipesection 40 is not needed and the bore hole is allowed to blow until thegas pocket has been depleted and when this condition occurs all of thisblow out preventing apparatus is removed from the tubing and taken toanother location. If, however, during the time which the gas from thepocket is blowing if sand starts it is merely necessary to close valve35 and install the upper pipe section 40, then open valve 35 and allowthe bore hole to blow to depletion.

While certain embodiments of the invention have been described forillustrative purposes the invention obviously is not limited thereto.

I claim:

1. Apparatus for preventing sand and gravel blow-out from a geophysicalexploration drill hole lined with a tubing and following discharge of anexplosive charge in the lower portion of said drill hole, comprising incombination, a pipe adapted at one end to be attached to the upperportion of said tubing, the other end of said pipe being closed, atleast one opening in the wall of said pipe, a funnel shaped deflectordisposed around said pipe and attached thereto at its small diameterend, the open end thereof being directed downward, and said deflectorsurrounding the pipe at the level of said opening in such a manner as todirect downward toward the earth, sand and gravel ejected from the pipethrough said opening.

2. The apparatus of claim 1 wherein the closed other end of said pipe isclosed by a hinged closure.

3. Apparatus for preventing sand and gravel blow-out from a geophysicalexploration drill hole lined with a tubing and following discharge of anexplosive charge in the lower portion of said drill hole, comprising incombination, a pipe adapted at one end to be attached to the upperportion of said tubing, at least one opening in the wall of said pipe, avalve communicating with the other end of said pipe, one end of anelongated second pipe communieating with the other end of said valve,the other end of said second pipe being closed, a generally funnelshaped deflector disposed coaxially with said first pipe in such amanner that the deflector surround-s said first pipe at the level ofsaid opening in said pipe and the large diameter open end of said funnelshaped deflector being directed downward in such a manner as to deflectgenerally downward sand and gravel ejected from said first pipe throughsaid opening.

4. The apparatus of claim 3 wherein the closed other end of said secondpipe is closed by a hinged closure.

References Cited in the file of this patent UNITED STATES PATENTS858,321 Auchu June 25, 1907 911,649 Elsey Feb. 9, 1909 941,452 HenningNov. 30, 1909 1,595,186 Gray Aug. 10, 1926 1,659,452 Welton Feb. 14,1928 1,858,241 Giles May 17, 1932 1,868,794 Fuller et a1 July 26, 19321,969,513 Kelley Aug. 7, 1934 2,387,770 Rogers et al Oct. 30, 1945

